Patent · US Expired

Method and apparatus for optically examining miniature patterns

US6327035A · kind A · utility

29Cited by
6References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 30, 1999
Grant dateDec 4, 2001
Priority date
Expiry dateNov 30, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70616
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method and apparatus for optically determining a physical parameter a pattern made up of features and disposed on an underlayer. The physical parameter can be, e.g., feature width, relative feature size, feature thickness, index of refraction n or extinction coefficient k and is determined from a response light generated upon illumination of the pattern and underlayer. The response light, e.g. light transmitted by or reflected from the pattern and from the underlayer is analyzed and broken down into response light fractions including an underlayer light fraction and a feature light fraction as well as any other background light fractions making up the response light. The physical parameter of the pattern is determined from the response light fractions and reference physical parameters) of the underlayer, which are either known a priori or determined.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.